What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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89Suburban

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pwtr02ss

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I did the bearings and seals on my old S10 with the G80 in there.

I didn't mess with the ring gear and crap, but i replaced every bearing and seal except for the ones in the spider gears.
Not hard, Youtube was my best friend.

What I want to learn is how to do the gearing stuff.
Doesn't look too hard, just very fiddly.
From what i gathered, you want two pinion bearings.
One to destroy (make it so you can take it off easily in order to set depth), and one to use in the final assembly...

When i did mine, the bearings were all shot.
Cages were paper thin.
I think it was a combo of too much gear oil (I thought it was a good thing)
and running it a good half quart low for an 800-mile road trip.. :chair:
yeah. I think with a few specialty tools it's very possible to DIY. Casey has one we are going to try our hands on at some point. If that goes smooth, we may tear into the one in the Camaro. I'm hesitant though, I think I will have to change the converter to a higher stall if I go to a lower gear. It only has a 3400 in it now but has 3.23 gear so that helps it a lot. I still get the cam jerk after lockup at 55 so if I put a lower gear, I think it'll make it a lot worse
 

Just Fishing

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yeah. I think with a few specialty tools it's very possible to DIY. Casey has one we are going to try our hands on at some point. If that goes smooth, we may tear into the one in the Camaro. I'm hesitant though, I think I will have to change the converter to a higher stall if I go to a lower gear. It only has a 3400 in it now but has 3.23 gear so that helps it a lot. I still get the cam jerk after lockup at 55 so if I put a lower gear, I think it'll make it a lot worse

Main one was a special puller and a slide hammer

Otherwise, I just used some cheap bearing and seal drivers.
(they show up in the "Frequently bought together)
1645284879547.png

For the pinion and diff carrier bearings, $20 at my local machine shop.
He swapped them out while I waited.

I pretty much just copied the current config down to the letter.
Used OEM bearings, and kept any spacers that were already there in place since i wasn't touching the ring gear.
I also marked the pinion & nut, counted the threads, and took pictures.
I put it back together exactly as it was.

Pinion felt a little easy to turn for being brand new, but i didn't have any issues.
I put a good 80k on the rear end afterwards.
Still going great, no vibrations and no leaks.

One day when i finally try my hand at a ring gear (I want to swap the diff out in the hoe, I want/need a locker).
I have a decent dial indicator.
Seems to be the same one that they use in most of the videos i have watched on the subject.
Grizzly brand...
 

89Suburban

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I did the bearings and seals on my old S10 with the G80 in there.

I didn't mess with the ring gear and crap, but i replaced every bearing and seal except for the ones in the spider gears.
Not hard, Youtube was my best friend.

What I want to learn is how to do the gearing stuff.
Doesn't look too hard, just very fiddly.
From what i gathered, you want two pinion bearings.
One to destroy (make it so you can take it off easily in order to set depth), and one to use in the final assembly...

When i did mine, the bearings were all shot.
Cages were paper thin.
I think it was a combo of too much gear oil (I thought it was a good thing)
and running it a good half quart low for an 800-mile road trip.. :chair:
I read horror stories in here about guys fighting the c-clips on this thing so this is not a fix it in the driveway myself option. Working my balls off too so I don't even have the time to do it if I wanted too. I replaced the spider gears on one of my old dodges once. Open diff peg legger did too many burn outs.
 

Just Fishing

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I read horror stories in here about guys fighting the c-clips on this thing so this is not a fix it in the driveway myself option. Working my balls off too so I don't even have the time to do it if I wanted too. I replaced the spider gears on one of my old dodges once. Open diff peg legger did too many burn outs.

I'm hoping it's just like the one on my S10
it uses full-sized axles.
Video i watched on the subject was for a Silverado.
Exact same setup that it has.

There is a bolt in the middle of the carrier.
10mm iirc
you then slide out a big pin that keeps the axles pushed out.
Assuming you can remove that, it's cake.

Push the axles in, then you can see the clip.
I used a magnet tool to grab it.
then the axles slide right out.
everything else comes apart easily.
 

89Suburban

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I'm hoping it's just like the one on my S10
it uses full-sized axles.
Video i watched on the subject was for a Silverado.
Exact same setup that it has.

There is a bolt in the middle of the carrier.
10mm iirc
you then slide out a big pin that keeps the axles pushed out.
Assuming you can remove that, it's cake.

Push the axles in, then you can see the clip.
I used a magnet tool to grab it.
then the axles slide right out.
everything else comes apart easily.


Yeah I read alot of bitching on here about getting the axle pushed in far enough to get the c-clips out on these.


I guess on the bright side, since all the fasteners on the rear end will be knocked loose form their 15 year slumber, so I can do a rear drop faster and easier.
 

pwtr02ss

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I just pulled the axles on the Camaro. I had to take the wheel speed sensor off to get the axle to slide in far enough to get the clips to fall off. I wonder if there's something similar on these? Like @Just Fishing said. Take the 10mm bolt out, pull the block out, push axle toward the center section and the clips fall off. I've never replaced the bearings but I have swapped the g80 after I broke a few in my car. Left spacers exactly where there were and had no issues. You're having to go deeper than I did though.
 

Doubeleive

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Sign post through the diff cover? :crazy:
No, they just don't hold up, completely broken. the worse that happened with the eaton is I wore the bearings out after 2 years, then it just needed bearings and good to go.
this was after what would be considered severe abuse.
this is how break downs typically go in order with the transmission being the weakest point, it can also go by mileage breakdown as the miles accumulate the farther down the list you get
1.transmission
2.differential carrier
3.pinion
4.universal joints
5.rear axle bearings/cv axle 1/2 shaft
6. transfer case (these are pretty hardy, might never break)
 

Just Fishing

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No, they just don't hold up, completely broken. the worse that happened with the eaton is I wore the bearings out after 2 years, then it just needed bearings and good to go.
this was after what would be considered severe abuse.
this is how break downs typically go in order with the transmission being the weakest point, it can also go by mileage breakdown as the miles accumulate the farther down the list you get
1.transmission
2.differential carrier
3.pinion
4.universal joints
5.rear axle bearings/cv axle 1/2 shaft
6. transfer case (these are pretty hardy, might never break)

Man you must be having some fun! :jester:


My beater is my old vette in my profile image.

I have a rule, I can have nice tires in the front.
but I can't go crazy with sticky tires in the rear...
Something about being able to spin the tires whenever i want.
IIRC it's a 3200rpm stall, right when the powerband starts to kick in.... :happy3:
If I were to do it over again, I would do a 4k stall...

the D36 I have is a known weak point on these.
Planning to run it until it breaks, but as long as I cheap out on tires I should be fine.
Upgrades are available out of standard transmission, but those go for like 2k last I checked.
 

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